Time before anti-Toxoplasma IgG seroconversion detection by 7 commercial assays in French pregnant women

Abstract

We assessed the ability to early detect a toxoplasmic seroconversion between 1 immunoblot (LDBIO II®) and 6 automated assays (TGS TA®, Architect®, Vidas II®, Liaison II®, Platelia®, and Elecsys®), comparing the time before anti-Toxoplasma gondii IgG detection during infection in pregnant women. From 2007 to 2015, 620 sera of 269 women were included. The median durations before positive IgG detection with Vidas II®, Liaison II®, Platelia®, and Elecsys® were significantly longer than Architect® with differential times from 11 to 28days (P<0.001). This time was significantly shortened by the use of LDBIO®, resulting in a saving of 13days (P<0.001). The detection of a positive rate of IgG with TGS TA® was as early as Architect® (P=0.105). The ability to early detect a toxoplasmic seroconversion is not equivalent between the assays and has to be considered when selecting the reagents to reduce the time to therapeutic intervention.

Keywords: Automated tests; Immunoblot; Immunodiagnosis; Pregnancy; Seroconversion; Toxoplasma gondii.